package com.easemob.helpdesk.widget.imageview;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.RectF;
import android.graphics.Xfermode;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.widget.ImageView;

import com.housekeeperapp.R;

import java.lang.ref.WeakReference;

/**
 * Created by liyuzhao on 16/10/10.
 */
public class RoundImageViewByXfermode extends ImageView {

    private Paint mPaint;

    private Xfermode mXfermode = new PorterDuffXfermode(PorterDuff.Mode.SRC_IN);

    private Bitmap mMaskBitmap;
    private WeakReference<Bitmap> mWeakBitmap;

    /**
     * 图片的类型,圆形or圆角
     */
    private int type;

    public static final int TYPE_CIRCLE = 0;
    public static final int TYPE_ROUND = 1;

    /**
     * 圆角大小的默认值
     */
    private static final int BORDER_RADIUS_DEFAULT = 10;

    /**
     * 圆角的大小
     */
    private int mBorderRadius;


    public RoundImageViewByXfermode(Context context) {
        this(context, null);
    }

    public RoundImageViewByXfermode(Context context, AttributeSet attrs) {
        super(context, attrs);
        mPaint = new Paint();
        mPaint.setAntiAlias(true);

        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.RoundImageViewByXfermode);
        mBorderRadius = a.getDimensionPixelSize(
                R.styleable.RoundImageViewByXfermode_borderRadius,
                (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, BORDER_RADIUS_DEFAULT,
                        getResources().getDisplayMetrics()));//默认为10dp

        type = a.getInt(R.styleable.RoundImageViewByXfermode_type, TYPE_CIRCLE); //默认为Circle
        a.recycle();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        /**
         * 如果类型是圆形,则强制改变View的宽高一致, 以小值为准
         */
        if (type == TYPE_CIRCLE){
            int width = Math.min(getMeasuredWidth(), getMeasuredHeight());
            setMeasuredDimension(width, width);
        }
    }

    @Override
    public void invalidate() {
        mWeakBitmap = null;
        if (mMaskBitmap != null){
            mMaskBitmap.recycle();
            mMaskBitmap = null;
        }
        super.invalidate();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        //缓存中取出bitmap
        Bitmap bitmap = mWeakBitmap == null ? null : mWeakBitmap.get();
        if (null == bitmap || bitmap.isRecycled()){
            //拿到Drawable
            Drawable drawable = getDrawable();
            //获取drawable的宽和高
            int dWidth = drawable.getIntrinsicWidth();
            int dHeight = drawable.getIntrinsicHeight();

            if (drawable != null){
                //创建bitmap
                bitmap = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
                float scale = 1.0f;
                //创建画布
                Canvas drawCanvas = new Canvas(bitmap);
                //按照bitmap的宽高，以及view的宽高，计算缩放比例；因为设置的src宽高比例可能和imageview的宽高比例不同，这里我们不希望图片失真；
                if (type == TYPE_ROUND){
                    // 如果图片的宽或者高与view的宽高不匹配，计算出需要缩放的比例；缩放后的图片的宽高，一定要大于我们view的宽高；所以我们这里取大值；
                    scale = Math.max(getWidth() * 1.0f / dWidth, getHeight() * 1.0f / dHeight);
                }else {
                    scale = getWidth() * 1.0F / Math.min(dWidth, dHeight);
                }
                //根据缩放比例,设置bounds,相当于缩放图片了
                drawable.setBounds(0, 0, (int)(scale * dWidth), (int)(scale * dHeight));
                drawable.draw(drawCanvas);

                if (mMaskBitmap == null || mMaskBitmap.isRecycled()){
                    mMaskBitmap = getBitmap();
                }

                //Draw Bitmap.
                mPaint.reset();
                mPaint.setFilterBitmap(false);
                mPaint.setXfermode(mXfermode);
                //绘制形状
                drawCanvas.drawBitmap(mMaskBitmap, 0, 0, mPaint);
                mPaint.setXfermode(null);
                //将准备好的bitmap绘制出来
                canvas.drawBitmap(bitmap, 0, 0, null);
                //bitmap 缓存起来,避免每次调用onDraw,分配内存
                mWeakBitmap = new WeakReference<Bitmap>(bitmap);
            }
        }
        // 如果bitmap还存在,则直接绘制即可
        if (bitmap != null){
            mPaint.setXfermode(null);
            canvas.drawBitmap(bitmap, 0.0f, 0.0f, mPaint);
            return;
        }
    }

    /**
     * 绘制形状
     */
    public Bitmap getBitmap() {
        Bitmap bitmap = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(bitmap);
        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        paint.setColor(Color.BLACK);

        if (type == TYPE_ROUND) {
            canvas.drawRoundRect(new RectF(0, 0, getWidth(), getHeight()), mBorderRadius, mBorderRadius, paint);
        } else {
            canvas.drawCircle(getWidth() / 2, getWidth() / 2, getWidth() / 2, paint);
        }
        return bitmap;
    }

}


